How did the periodic table become one of most important parts of chemistry? In this article, we will look into how the periodic table was first formed and how it evolved as the years passed.
Image 1: Current periodic table
How was the periodic table first created?
The formation of the periodic table all started back in 1789. A French chemist named Antoine Lavoisier tried grouping the elements based on their properties into gases, non-metals, metals and earth. Forty years later, in 1829, German physicist Johann Wolfgang Döbereiner observed the similarities of certain elements and arranged them groups of three (Such as lithium, sodium, and potassium) in increasing order of atomic weight and called them "triads". By observing some properties of the middle element, he could approximate the average value of these properties in the other two in each triad.
The Breakthrough
In 1860, a revised list of elements was published at the first international conference in Karlsruhe, Germany. At that specific conference, it was concluded that the periodic table should have an arrangement with increasing atomic mass. John Newlands, a British chemist, also noticed that the similarities between elements with atomic weights differed by seven which he called the Law of Octaves, drawing a comparison with the octaves of music.
Creation of the modern periodic table
Image 2: the first periodic table (created by Dmitri Mendeleev)
In 1869, Dmitri Mendeleev, a Russian chemist, came to prominence with his tabular diagram of the known 63 elements. This became the basic ingredient list, of which all matter exists, and now it is known as the periodic table. One year later, Lothar Meyer, a German chemist, created a similar periodic table and recognised the periodic trends in the properties of elements.
Fast forward
As time passed, scientists continued to discover more elements and the periodic table continued to grow.
1890s - The noble gases are discovered. This is a group of elements such as helium that don’t like to react with other elements.
1940s - Scientists found many new elements by colliding atoms or pieces of atoms.
2018 - Chemists confirmed four elements (Nihonium, Moscovium, Tennessine, Oganesson) that had never been observed before. With these additional four elements, this brought to the 118 known elements, completing the 7th row of the periodic table.
Personal Opinion
The periodic table is the base of chemistry. We need to know that through the years, lots of scientists have worked together to put together this chart that can be easily interpreted and understood. Lots of information are put in the periodic table and we should use them promptly for future experiments or findings.
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